Illness & Symptoms
Skin Lump
Is this your child's symptom?
- A skin lump or bump covered by normal skin
 - Skin swelling just in one spot (localized) is also included
 
Causes of Skin Lumps
- Insect Bites. The most common cause of an itchy bump is a mosquito bite. Other insects can also cause little bumps.
 - Stings. A bee sting can cause a painful bump. The swelling can become quite large.
 - Lymph Nodes. Most common cause of a lump or mass felt under the skin. Commonly found in the neck or groin. Nodes have a boundary or edge and are movable. This is not the case for the swelling seen with insect bites. Lymph nodes become larger with infections.
 - Scalp Hematoma. The most common cause of a lump on the head is a scalp hematoma (goose egg). In a child under 2 years of age the injury may not have been seen.
 - Injuries. New lumps anywhere can be caused by an injury that wasn't observed. A bruise is often present with the swelling.
 - Callus. Broken bones heal with new bone formation. The medical term is callus. The callus feels like a bony knot that is larger than the bone itself. A callus is most commonly felt after a collarbone fracture.
 - Boils. A boil is a skin abscess. It causes a very painful red lump.
 
Lumps that are a Normal Part of the Body
- Breast Bud. A small disc-shaped lump felt under the nipple. It indicates the onset of puberty in 7-12 year old girls.
 - External Occipital Protuberance. The bony lump felt at the base of the skull in back.
 - Mastoid Process. The bony lump felt behind each lower ear.
 - Xiphoid Process. A small hard lump felt at the lower end of the sternum (breastbone).
 
Common Objects Used to Guess the Size
- Pea or pencil eraser: ¼ inch or 6 mm
 - Dime: ¾ inch or 1.8 cm
 - Quarter: 1 inch or 2.5 cm
 - Golf ball: 1 ½ inches or 3.8 cm
 - Tennis Ball: 2 ½ inches or 6.4 cm
 
When to Call for Skin Lump
 Call Doctor or Seek Care Now
  |  
  Contact Doctor Within 24 Hours
 Contact Doctor During Office Hours
  |  
  Self Care at Home
  |  
Call Doctor or Seek Care Now
- Redness spreading from the lump with fever
 - Groin swelling and painful
 - Age less than 12 months and on scalp. Exception: normal bump in back at base of skull.
 - Your child looks or acts very sick
 - You think your child needs to be seen, and the problem is urgent
 
Contact Doctor Within 24 Hours
- Redness spreading from the lump without fever
 - Boil suspected (painful, non-itchy, red lump)
 - Age 12 months or older and on scalp. Exception: normal bump in back at base of skull.
 - Can't move nearest joint normally (bend and straighten completely)
 - Swelling is painful and cause not known
 - You think your child needs to be seen, but the problem is not urgent
 
Contact Doctor During Office Hours
- Large lump more than 1 inch (2.5 cm) and cause not known
 - Small lump lasts more than 7 days and cause not known
 - You have other questions or concerns
 
Self Care at Home
- Small lump present 7 days or less and cause not known. Reason: probably due to insect bite not observed.
 - Breast bud - normal lump under the nipple
 - External occipital protuberance - normal lump on back of head
 - Mastoid process - normal lump behind each lower ear
 - Xiphoid process - normal lump at bottom of breastbone
 
Care Advice
Treatment for a Small Lump or Swelling
What You Should Know:
- Most new swellings are due to insect bites. Mosquito bites account for 90% of them. Your child may not even know that he got bit.
 - Suspect an insect bite if there are bites on other parts of the body.
 - While most insect bites cause a small red bump, some are larger (like a hive).
 - This does not mean your child has an allergy or the bite is infected.
 - Here is some care advice that should help.
 
Cold Pack For Swelling:
- Apply a cold pack or cold wet washcloth for 20 minutes.
 
Steroid Cream for Itching:
- If the swelling is itchy, use 1% hydrocortisone cream (such as Cortaid). No prescription is needed.
 - Do this 3 times per day.
 
Allergy Medicine for Itching:
- If itching becomes severe, give a dose of Benadryl.
 - No prescription is needed. Age limit: 1 and older.
 
What to Expect:
- Most insect bites itch or hurt for 1 or 2 days.
 - The swelling usually peaks in 2 days, but may last a week.
 - If the swelling becomes larger or doesn't go away, it needs to be examined.
 
Call Your Doctor If:
- Swelling becomes very painful
 - Fever occurs
 - Swelling becomes large (over 1 inch or 2.5 cm)
 - Swelling lasts over 7 days
 - You think your child needs to be seen
 - Your child becomes worse
 
Lumps that are a Normal Part of the Body
Breast Buds - Normal Lump Under the Nipple:
- Breast buds are normal, small disc-shaped rubbery lumps felt under the nipple.
 - Age. They normally occur in 8-12 year old girls and are the first sign of puberty. Sometimes, they are even normal in 7 year olds.
 - One Side. They sometimes start just on one side. Don't worry about that. Within 2 or 3 months, a breast bud will also appear on the other side.
 - Importance. The entire breast develops entirely from the breast bud, taking 2 or 3 years to completion.
 - Symptoms. Breast buds normally can be somewhat tender.
 - Caution: Never squeeze or massage breast buds. Reason: Can cause a serious infection.
 - Risks. None. Breast buds have no risk of turning into cancer.
 - Follow-up. You can have your child's doctor check the breast bud during the next regular office visit.
 
External Occipital Protuberance - Normal Lump on Back of Head:
- The lump you feel at the base of the skull in back is normal. It is a bony part of the skull that sticks out and feels hard.
 - If you feel carefully, you will find one on yourself or other children.
 - This is not caused by any injury.
 
Mastoid Process - Normal Lump Behind the Ear:
- The mastoid process is a bony lump you can feel behind the lower ear.
 - Muscles that turn the neck attach to the mastoid process.
 - The process is larger in men because of larger neck muscles.
 - The mastoid is filled with air cells that connect to the inner ear.
 
Xiphoid Process - Normal Lump at Bottom of Breastbone:
- The small hard lump at the lower end of the sternum (breastbone) is normal. It is called the xiphoid process. You can feel it.
 - It is more prominent in babies and slender children. Sometimes, it's more visible when breathing in.
 - If you feel carefully, you will find one on yourself or other children.
 - It's made of cartilage, but turns to bone in adults.
 
Call Your Doctor If:
- You have other questions or concerns
 
Remember! Contact your doctor if you or your child develop any "Contact Your Doctor" symptoms.
Disclaimer: this health information is for educational purposes only. You, the reader, assume full responsibility for how you choose to use it.
Copyright 2000-2025 Schmitt Pediatric Guidelines LLC.
Reviewed: 5/1/2025 Updated: 1/25/2025

